Internet suppliers at home and abroad all concern overall disk capacity of their own service cluster. Through the concern of the disk capacity, the disk capacity may be increased or decreased at proper time, thereby saving a lot of costs and bringing about huge economic benefits.
In the prior art, a threshold value is preset for the disk capacity of the cluster. After the disk capacity reaches the threshold value, the number of increased machines is predicted manually and increased manually. However, since this disk capacity expansion manner requires manual prediction and increase, it consumes greater manpower cost. Furthermore, as an accuracy of manually-predicted disk capacity trend is lower, the disk capacity after the increase cannot meet the need or becomes redundant and thereby causes waste.